Heading inside The magical size bracelet chapter 12 by SatireMarker

You decided that it was time to do what frankly seemed inevitable. You would go inside Tread's underwear. You waited for a brief lull in his tumultuous stretches and, still pinned mostly to the ground, reached the bracelet with your other arm. There, you increased your speed, which in turn slowed down everything around you. The giant teen now moved at a speed more appropriate for his gargantuan size. That allowed you to perform your next move, which was tricky, more easily. Grabbing the threads of the tight underwear you were pinned to, you looped your arms inside, securing your grip while allowing you to use the bracelet. Sticking your tongue out in concentration you fiddled with the controls and looping your arms through them, you shrunk yourself down even more. At normal speed something so precise would be borderline impossible because any of Tread's hectic movements would have thrown you completely out of whack. Now, with the Hawaiian teen moving in slow motion, you could do as you liked. You fiddled with the controls, allowing yourself to shrink and vault between the tiny holes in the fabric; once you were through, touching the delightfully warm skin of his left arse cheek, you set the bracelet to put you back at an inch; still unnoticeable and invincible, you were pressed tight, squeezed between his arse and the tight, speedo-esque underwear. It was incredible!